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Urban environments are increasing worldwide and are inherently different than their rural counterparts, with a variety of effects on wildlife due to human presence, increased habitat fragmentation, movement barriers, and access to anthropogenic food sources. Effective management of urban wildlife requires an understanding of how urbanization affects their behavior and ecology. The spatial activity and interactions of urban wildlife, however, have not been as rigorously researched as in rural areas. From January 2015 to December 2016, we captured, radio-collared, and tracked 11 coyotes and 12 red foxes in Madison, WI. Within our study area, coyotes strongly selected home ranges with high proportions of natural areas; conversely, red foxes selected home ranges with open space and moderately developed areas. Use of highly developed areas best explained variation among individual home range sizes and inversely affected home range size for coyotes and red foxes. Coyote and red fox home ranges showed some degree of spatial and temporal overlap, but generally appeared partitioned by habitat type within our study area. Coyotes and red foxes were both active at similar times of the day, but their movement patterns differed based on species-specific habitat use. This spatial partitioning may promote positive co-existence between these sympatric canids in urban areas, and our findings of spatial activity and interactions will better inform wildlife managers working in urban areas.

Pumas (Puma concolor) and black bears (Ursus americanus) are large carnivores that may influence scavenger population dynamics. We used motion-triggered video cameras deployed at deer carcasses to determine how pumas and black bears affected three aspects of carrion acquisition by scavengers: presence, total feeding time, and mean feeding-bout duration. We found that pumas were unable to limit acquisition of carrion by large carnivores but did limit aspects of carrion acquisition by both birds and mesocarnivores. Through their suppression of mesocarnivores and birds, pumas apparently initiated a cascading pattern and increased carrion acquisition by small carnivores. In contrast, black bears monopolized carrion resources and generally had larger limiting effects on carrion acquisition by all scavengers. Black bears also limited puma feeding behaviors at puma kills, which may require pumas to compensate for energetic losses through increasing their kill rates of ungulates. Our results suggest that pumas provide carrion and selectively influence species acquiring carrion, while black bears limit carrion availability to all other scavengers. These results suggest that the effects of large carnivores on scavengers depend on attributes of both carnivores and scavengers (including size) and that competition for carcasses may result in intraguild predation as well as mesocarnivore release.

Scavenging is a widespread behaviour and an important process influencing food webs and ecological communities. Large carnivores facilitate the movement of energy across trophic levels through the scavenging and decomposition of their killed prey, but competition with large carnivores is also likely to constrain acquisition of carrion by scavengers. We used an experimental approach based on motion-triggered video cameras at black-tailed deer (Odocoileus hemionus columbianus) carcasses to measure the comparative influences of two large carnivores in the facilitation and limitation of carrion acquisition by scavengers. We found that pumas (Puma concolor) and black bears (Ursus americanus) had different effects on their ecological communities. Pumas, as a top-level predator, facilitated the consumption of carrion by scavengers, despite significantly reducing their observed sum feeding times (165.7 min ± 21.2 SE at puma kills 264.3 min ± 30.1 SE at control carcasses). In contrast, black bears, as the dominant scavenger in the system, limited consumption of carrion by scavengers as evidenced by the observed reduction of scavenger species richness recorded at carcasses where they were present (mean = 2.33 ± 0.28 SE), compared to where they were absent (mean = 3.28 ± 0.23 SE). Black bears also had large negative effects on scavenger sum feeding times (88.5 min ± 19.8 SE at carcasses where bears were present, 372.3 min ± 50.0 SE at carcasses where bears were absent). In addition, we found that pumas and black bears both increased the nestedness (a higher level of order among species present) of the scavenger community. Our results suggest that scavengers have species-specific adaptions to exploit carrion despite large carnivores, and that large carnivores influence the structure and composition of scavenger communities. The interactions between large carnivores and scavengers should be considered in future studies of food webs and ecological communities.

The spatial scale at which organisms respond to human activity can affect both ecological function and conservation planning. Yet little is known regarding the spatial scale at which distinct behaviors related to reproduction and survival are impacted by human interference. Here we provide a novel approach to estimating the spatial scale at which a top predator, the puma (Puma concolor), responds to human development when it is moving, feeding, communicating, and denning. We find that reproductive behaviors (communication and denning) require at least a 4× larger buffer from human development than non-reproductive behaviors (movement and feeding). In addition, pumas give a wider berth to types of human development that provide a more consistent source of human interference (neighborhoods) than they do to those in which human presence is more intermittent (arterial roads with speeds >35 mph). Neighborhoods were a deterrent to pumas regardless of behavior, while arterial roads only deterred pumas when they were communicating and denning. Female pumas were less deterred by human development than males, but they showed larger variation in their responses overall. Our behaviorally explicit approach to modeling animal response to human activity can be used as a novel tool to assess habitat quality, identify wildlife corridors, and mitigate human-wildlife conflict.

Human activity and development have a variety of effects on wildlife behavior, often prompting urban wildlife to adopt behavioral strategies—including spatiotemporal activity adjustments—that facilitate persistence in human‐dominated environments. In this study, our objective was to determine whether and how visitation behavior of raccoon dogs (Nyctereutes procyonoides) to communal scent marking hubs (i.e., latrines) was influenced by human activity and development in urban green spaces in Tokyo, Japan. Using camera‐trap data collected over 4530 trap days, we recorded 3259 latrine visits and assessed temporal patterns of activity at both the green space and individual latrine scales. We found that raccoon dog visitation to latrines was primarily at night in the urban green spaces, but the peak times for visitation at each latrine varied depending on the environmental context of the green space (size and the surrounding environment) and the latrines (the distance from a road). Our findings indicate that while raccoon dogs maintain scent‐marking behavior in urban areas, they exhibit behavioral flexibility through adjusting the timing of visitation to minimize disturbance from human activity. Our results underscore the importance of considering the spatiotemporal behavioral adaptations of urban wildlife and highlight the need to preserve accessible and temporally buffered areas for olfactory communication in human‐dominated areas. The diurnal pattern of latrine visits by raccoon dogs for each study site‐year based on kernel density estimates. Dashed vertical lines indicate the annual mean times of sunset and sunrise, and dotted vertical lines indicate the mean times at 21:00, 0:00, and 3:00.

Scavenging is a common feeding behavior that provides ecosystem services by removing potentially infectious waste from the landscape. The importance of facultative scavenging is often overlooked, but likely becomes especially important in ecosystems without obligate scavengers. Here, we investigated the ecological function of vertebrate facultative scavengers in removing ungulate carcasses from Japanese forests that lack obligate scavengers. We found that mammals detected carcasses first more often than birds, and that raccoon dogs ( Nyctereutes procyonoides ) were the most frequent scavenger to first detect carcasses. However, we found no evidence of there being species that signal the location of carrion to other species via social cues. Instead, higher temperatures promoted earlier detection of the carcasses by scavengers, likely related to increased olfactory signals. The carcasses were completely consumed on average in 7.0 days, reasonably similar to other systems regardless of habitat, indicating that facultative scavengers are providing ecosystem services. Larger carcasses tended to take longer to deplete, but carcasses were consumed faster in warmer temperatures. Our results indicate that facultative scavengers were capable of consuming carrion and contributing ecosystem services in a forest ecosystem that lacks obligate scavengers.

Mate selection influences individual fitness, is often based on complex cues and behaviours, and can be difficult to study in solitary species including carnivores. We used motion-triggered cameras at 29 community scrapes (i.e. scent marking locations used by multiple individuals) and home range data from 39 GPS-collared pumas (Puma concolor) to assess the relevance of communication behaviours for mate selection by female pumas in California. Female pumas visited community scrapes irregularly and visitation bouts appeared to be correlated with oestrus. Female pumas on average selected from 1.7 collared males, and selection was based on multiple cues that varied among the different time periods measured (i.e. the female's visitation bout and in 90 days previous to the consorting event). Female mate selection over the course of a visitation bout was based on frequency of the male visitation, mass, and age. In the 90 days previous to consorting, the number of scrapes a male created was the most important contributor to selection, which was likely related to his residency status. We also found that at least 14% of females mated with multiple males, thus possibly confusing paternity. Our findings provide a mechanistic understanding of how female pumas use scent and auditory communication at community scrapes to select dominant resident males to mate with.

Catch-per-unit-effort (CPUE) is often used to monitor wildlife populations and to develop statistical population models. Animals caught and released are often not included in CPUE metrics and their inclusion may create more accurate indices of abundance. We used 21 years of detailed harvest records for bobcat (Lynx rufus) in Wisconsin, U.S.A., to calculate CPUE and 'actual CPUE' (ACPUE; including animals caught and released) from bobcat hunters and trappers. We calibrated these metrics to an independent estimate of bobcat abundance and attempted to create simple but effective models to estimate CPUE and ACPUE using harvest success data (i.e., bobcats harvested/available permits). CPUE showed virtually no relationship with bobcat abundance across all years, but both CPUE and ACPUE had stronger, non-linear, and negative relationships with abundance during the periods when the population was decreasing. Annual harvest success strongly predicted composite ACPUE and CPUE from hunters and trappers and hunter ACPUE and CPUE but was a poorer predictor of trapper ACPUE and CPUE. The non-linear, and sometimes weak, relationships with bobcat abundance likely reflect the increasing selectivity of bobcat hunters for trophy animals. Studies calibrating per-unit-effort metrics against abundance should account for population trajectories and different harvest methods (e.g., hunting and trapping). Our results also highlight the potential for estimating per-unit-effort metrics from relatively simple and inexpensive data sources and we encourage additional research into the use of per-unit-effort metrics for population estimation.

Mortality causes and survival rates often vary between the geographically disparate populations of a species. Fishers (Pekania pennanti) are a mesocarnivore inhabiting forested areas across Canada and the United States of America. Due to their economic and ecological value, fishers have become the focus of many management and conservation efforts. However, a clear understanding of influential demographic parameters and pressures exerted on disparate populations is necessary for such discussions. We conducted a literature review of peer‐reviewed studies investigating fisher cause‐specific mortalities and survival to (a) synthesize the current available knowledge, (b) assess differences in cause‐specific mortalities and the sex‐specific adult survival rates between western fisher populations (i.e., populations from California, Oregon, Washington, or British Columbia) and eastern fisher populations (i.e., elsewhere in their distribution), and (c) identify potential gaps in the literature. We identified 26 studies between 1994–2024 describing cause‐specific mortality (n = 4), survival rates (n = 15 studies), or both (n = 7), with 20 studies assessing western fisher populations. There were significant differences between the cause‐specific mortalities for fishers in the eastern and western populations. Western fishers had higher mortality from predation and lethal toxicant exposure, while eastern fishers had higher mortality from legal harvest. Survival rates of males and females were not significantly different between the eastern and western populations; however, we found that male survival rates in the western populations varied considerably between studies. The geographic concentration of recent research presents a lack of information regarding the species outside of western populations, which may hinder management efforts throughout their range. Western fisher populations have been the focus of many recent studies and exhibit differences in cause‐specific mortalities but not in survival rates when compared to eastern fisher populations. Western fisher mortalities were dominated by predator attacks while eastern fisher mortalities were dominated by harvest.

Northern raccoons (Procyon lotor; hereafter raccoon) are a widely distributed mesocarnivore that is common throughout North and Central America. Already the source of many human–wildlife conflicts, recent range expansions and abundance increases may cause additional management issues. However, raccoons adapt their behavior and site use to their surroundings, necessitating further research into the factors driving raccoon site use intensity in less studied systems. To address this, we used camera traps to collect data on raccoons at 95 forest and grassland sites between December 2021 and May 2023 across the state of Illinois, USA (149,996 km2), and applied a Bayesian N‐mixture modeling approach to investigate factors driving raccoon site use intensity at two spatial scales: patch (100 m) and landscape (1 km). We included factors that we a priori hypothesized would affect raccoon site use intensity, including habitat, anthropogenic influences, and interspecific interactions. We collected 8634 photographs of raccoons over 13,948 trap nights and observed raccoons at 95.8% of all survey sites. At the patch scale, raccoon site use intensity decreased as impervious surface area (i.e., constructed materials that do not allow water to infiltrate the ground) increased and increased as road density increased. At the landscape scale, raccoon site use intensity also decreased as impervious surface area increased and increased as distance to nearest habitat edge increased. The effect of impervious surface area was over three times stronger than the other modeled factors at both spatial scales. These results contrast with some previous research regarding the effects of environmental factors on raccoons. Our findings highlight how anthropogenic influences (i.e., impervious surface, road density) and habitat characteristics were more influential than interspecific interactions on raccoons in forest and grassland areas. Management and conservation efforts involving raccoons need to account for the variable nature of the species and how natural land cover types may affect raccoon behavior or site use.